WASHINGTON (CNN) -- Hundreds of people across the country have been arrested by law enforcement officials targeting crooked mortgage brokers, real estate agents, and other industry officials, the head of the FBI and a top Justice Department official said Thursday.

FBI Director Robert Mueller and Deputy Attorney General Mark Filip announced the arrests the same day two former Bear Stearns hedge fund managers, Ralph Cioffi and Matthew Tannin, surrendered to the FBI. The men are expected to face federal charges that they intentionally misled investors in two funds that collapsed last summer under the weight of wrong-way bets on mortgage-backed securities.

More than 400 people have been charged in the mortgage fraud probe, of whom nearly 300 have been arrested, including 60 in a coordinated sweep Wednesday, the Justice Department said.

The losses in the mortgage fraud cases cost consumers more than $1 billion, Mueller said.

Many agencies were credited as contributing to the investigation, including the Internal Revenue Service, the Secret Service, the Department of Housing and Urban Development, immigration and customs agencies, postal inspectors and the Federal Deposit Insurance Corporation.

Most of the arrests came Wednesday, federal law enforcement officials said, in Miami, Houston, San Antonio, Baltimore, Chicago, and other cities.

Officials indicated the suspects were involved mostly in small-scale schemes.